F&M leak

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Jr.CubBuilder
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Joined: Thu Aug 12, 2004 10:33 pm

F&M leak

Post by Jr.CubBuilder »

I put on an F&M filter conversion, using their supplied gasket, and it's a pretty slick setup. However, it weeps a little bit of oil where it buts against the case, has anyone else experienced this?
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jlwild
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Post by jlwild »

Jr.Cub Builder,

:D I have had not problems with my F&M filter conversion. Now have +/- 100 hours on the unit. However, did follow F&M instructions and retorqued unit after 5-10 (?) hours.

Did you check case carefully prior to installation?

Suggest you retorque the unit and check for leaks. If still present, recommend changing the gaskets at next oil change.

Good luck, Jim W.
Jim Wildharber, Kennesaw, GA
Past President TIC170A (2010-12) and Georgia Area Representative
'55 170B, N3415D, SN:26958, O-300D; People's Choice '06 Kelowna, B.C., Best Modified '07 Galveston, TX, Best Modified '08 Branson, MO.
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cessna170bdriver
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Post by cessna170bdriver »

The most likely cause of a leak at the case would be inadequate torque on the nut. I don't remember the torque right off hand, but it is substantial, somewhere in the neighborhood of 50-70 ft-lbs, as opposed to the 200 or so in-lbs for the screen. It definitely was a higher torque than I would have applied without a torque wrench.

The filter adapter tends to turn when torquing the nut, so I found it easiest to put the filter can in place as a hand hold. I stood on the right side of the airplane and held the filter can in place (both hands with fingers interlocked behind) while someone else pulled on the torque wrench from the left side.

I got 38 psi (according to the aircraft gauge) with a pre-oiler, and upwards of 50 psi in a 5-minute run and no noticable leaks in the adapter... yet.
Miles

“I envy no man that knows more than myself, but pity them that know less.”
— Thomas Browne
Jr.CubBuilder
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Post by Jr.CubBuilder »

yeah I'm pretty sure it was 65lbft of torque, and I got that after some persistence with a crows foot. I'm wondering if the weep would stop at the next annual with just a slight coat of sealant on both sides of a new gasket.
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johneeb
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Post by johneeb »

Jr.CubBuilder wrote:yeah I'm pretty sure it was 65lbft of torque, and I got that after some persistence with a crows foot. I'm wondering if the weep would stop at the next annual with just a slight coat of sealant on both sides of a new gasket.
Dear Mr CubBuilder,

F & M used to offer to loan Customers a thread chaser to clean carbon that has built up in the previously unused threads that the new F & M adapter screws into. This carbon in known to cause problems acheaving a proper seal of the gasket at the accessory cover end or the copper crush washer on the outside end, as you maybe troqueing against the afomentioned carbon rather than drawing down the stack. This is the voice of "Been there Done That" talking. :P
Last edited by johneeb on Thu Jun 15, 2006 1:38 pm, edited 1 time in total.
John E. Barrett
aka. Johneb

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N2865C
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Post by N2865C »

I installed a FM filter recently and asked about the chaser. They did have one available to loan, but in my case with a low time engine they said it would not be necessary. They were very helpful on the phone. Give them a call.
John
N2865C
"The only stupid question is one that wasn't asked"
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GAHorn
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Post by GAHorn »

johneeb wrote:
Jr.CubBuilder wrote:yeah I'm pretty sure it was 65lbft of torque, and I got that after some persistence with a crows foot. I'm wondering if the weep would stop at the next annual with just a slight coat of sealant on both sides of a new gasket.
Mr CubBuilder,

F & M used to offer to loan Customers a thread chaser to clean carbon that has built up in the previously unused threads that the new F & M adapter screws into. This carbon in known to cause problems acheaving a proper seal of the copper crush washer, as you maybe troqueing against the afomentioned carbon rather than drawing down the copper crush washer. This is the voice of Been there Done That talking. :P
The copper "crush" washer does not fit between the adaptor and the accy case. A special fiber washer/gasket is to be placed at the base of the unit, and the copper gasket goes at the outboard-end.
'53 B-model N146YS SN:25713
50th Anniversary of Flight Model. Winner-Best Original 170B, 100th Anniversary of Flight Convention.
An originality nut (mostly) for the right reasons. ;)
Jr.CubBuilder
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Post by Jr.CubBuilder »

gahorn wrote:The copper "crush" washer does not fit between the adaptor and the accy case. A special fiber washer/gasket is to be placed at the base of the unit, and the copper gasket goes at the outboard-end.
That's the way I installed mine. It's the fiber gasket that is weeping, I'll try setting the torque again next time I get the cowling off, and I'll see what F&M suggests.
Haydon
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F&M Oil Filter Unit

Post by Haydon »

Many Thanks to the contributors to this thread... In a few minutes I will be installing the new F&M unit on my 170A. Your advice on this installation is much appreciated. I will be certain to torque and re-torque !!
Richard Haydon
'49 170A
Ducote Airpark TS65
Haydon
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Follow up to F&M installation

Post by Haydon »

I just wanted to add my 2 centavos worth to this thread.... I highly recomend the F&M kit. I believe that the "thread cleaning tap" should be mandatory when installing the kit. I requested it and it was mailed with the kit. F&M requests that you ship it back to them after installing the oil filter adaptor. The advice that Miles has given on this thread is very correct.... Have a friend available to hold the outside housing of the filter adaptor when applying to torque to the assembly. A 1" crow foot will work on a torque wrench. A socket would be better and I would like to see F&M include that with their loaner tap. Many Thanx to all !!

Richard......
Richard Haydon
'49 170A
Ducote Airpark TS65
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